Effect of Pr substitution on structural and electrical properties of BiFeO3 ceramics

• XRD patterns infer triclinic (P1) of Pr-doped BiFeO3 (0.15 ≤ x ≤ 0.25).
• Raman spectra reveal suppression of ferroelectric behavior due to Pr doping.
• Changes in Raman normal modes are noticed with increasing doping concentration.
• Room temperature ε′ values are ≅65, 82 and 95 for x = 0, 0.15, 0.25 at 1 MHz.

Investigation on structural, vibrational, dielectric and ferroelectric properties of Bi1−xPrxFeO3 (x = 0.0, 0.15, 0.25) ceramic samples has been carried out. Room temperature Rietveld-refined X-ray diffraction pattern shows the crystal structure of Bi1−xPrxFeO3 is rhombohedral for x = 0 and triclinic for x = 0.15, 0.25. The changes in Raman normal modes with increasing doping concentration infer the structural transformation is due to Pr substitution at A-site in BiFeO3. Raman spectra also reveal suppression of ferroelectric behavior due to Pr doping. The dielectric parameters, namely, dielectric permittivity (ε′) and loss tangent (tan (δ)) were evaluated as a function of frequency at room temperature. The ferroelectric polarization reduces in Pr doped bulk BFO samples due to structural change.

Representations of room temperature (a) rhombohedral BiFeO3 and (b) triclinic structure of Bi1−xPrxFeO3.Figure optionsDownload as PowerPoint slide